The initial collection of the National and University Library "St. Kliment Ohridski" amounts 150,000 library units, mostly university textbooks and scientific publications in the field of humanities and social sciences: literature, ethnology, geography, history, etc., and also, significant titles from the reference literature (encyclopedias, dictionaries, bibliographies) and approximately 300 titles periodicals.

In 1945, with the Decision of ASNOM, the NUL began to receive a copy of all items published in Macedonia and also in the former Yugoslavia.

Today, through COBISS.Net, the VLM Center provides connection and cooperation with more than 700 participating libraries in the COBISS systems of Slovenia, Serbia, Monte Negro, Bosnia and Herzegovina, Bulgaria and Albania.

The library is a member of several international associations and bodies among which are: IFLA, CENL, LIBER, EBLIDA, ISSN, ISBN, ISMN.

In line with this, the National center for ISSN and National Agency for ISBN, International Agency for ISMN as well the centre for international landing of library materials and E-CRIS – center that compiles and updates data on research organisations, research projects and scholars in the Republic of Macedonia, function within the library.

At the beginning of 2008 the foundation stone of new and modern building as an extension of the current one was laid by which the library has received additional 3000 m2.